<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

    <!-- script标签内，写js代码-->
<!--    <script>-->
<!--        alert('hello world');-->
<!--    </script>-->
    <script src="js/Map和Set.js"></script>

</head>
<body>

<!--这里也可以放js-->
</body>
</html>